BOARD MATERIAL AND BUILDING MATERIAL UTILIZING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a board material and a building material utilizing the same which is capable of sufficiently corresponding to the rapid change in the external temperature atmosphere such as solar radiation. SOLUTION: Medium-density fiberboard 1 has baserock layers respectively on the surface and the rear. Pressing temperature is set in a range within 30-60 deg.C for the baserock layer on one side and pressing temperature on the other side is set higher than it by 40-150 deg.C and pressing is performed from the surface and the rear of the medium-density fiberboard 1. The surface having the baserock layer on the low temperature side is made to a projected warpage by difference of expansion coefficient. Further, specific gravity of the bedrock layer is 0.8-1.4 and average specific gravity of the board is 0.35-0.8. Furthermore building material is provided by sticking a sheetlike material 2 on the surface of at least one hand in such a state that temperature difference of the surface and the rear of the board material is regulated to 5-50 deg.C.